If you use an actual blower intake rather than one adapted/modifed from a 4 barrel intake, it's a bolt-on that eliminates the valley pan gasket. You just use port gaskets and RTV on the end rails. They're around $500 but the way to go. Usually have a provision for a pop-off valve built in.
Dyers is good, Good Vibrations Motorsports (who I really like) or RBS for other parts. BDS is okay. There are other suppliers like The Blower Shop who are pretty proud ($$) or their stuff.